On St. Martin, you will find two personalities on one small island. The more relaxed side of the island is St. Martin (French), where you can shop chic boutiques, sample the absolute best in culinary delights and relax on plenty of white-sand solitude.
If you're in the mood for a little more excitement, the Dutch side (St. Marteen) offers a more cosmopolitan flair with brightly-lit casinos, classy nightclubs and plenty of duty-free shopping. In addition to great Caribbean activities like white-sand beaches, haute cuisine, and a bit of European culture and architecture, St. Martin/St. Maarten is known for its shopping. On the French side in the capital, Marigot, you'll find European fashions, fragrances, an amazing selection of leather items and gold jewelry as well as cigars and liquors at duty free prices. Every Saturday and Wednesday, the waterfront plaza area bustles with locally grown foods, crafts and tourist souvenirs (t-shirts, hats, curios, etc.).
The Dutch side offers shopping opportunities in downtown Philipsburg, including electronics and photography supplies along with items similar to what you will find on the French side.
The best time to go in town is on Saturdays or weekdays when only one or two cruise ships are in port. Everything is closed on Sundays unless there is a ship in port. Even then, you would find only a small number of stores open.